Se-parable link chain



J. C. LAW

SEPARABLE LINK CHAIN.

APPLICATION FILED MAR-9,1921.

Patented Nov. 15, 1921.

3 SHEETS-SHEET 1- J. C. LAW.

SE'PARABLE LINK C HAIN.

APPLICATION FILED MAR-9,1921.

1,397,131, Patented Nov. 15,1921.

3 SHEETS-SHEET 2.

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.l. C. LAW.

SEPARABLE LINK CHAIN.

APPLICATION FILED MAR 9, 1921.

Patented Nov. 15, 1921. 3 SHEETS-SHEET a.

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; UNITED STATES" PATENT OFFICE.

JAMES C. LAW, OF SCRAN TON, PENNSYLVANIA, ASSIG'NOE TO WILMOT ENGINEERING COMPANY, OF HAZLETON, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

SEPARABLE-LINK 01mm.

Application filed March 9,

To all whom it may concern:

Be it known that I, J AMns C. LAW, a citizen of the United States, residing at Scranton, in the county of Lackawanna and State of Pennsylvania, have invented certain new and useful Improvements in separable-Link Chains, of which the following is a specification.

This invention relates to driving or sprocket chains of the type in which the links are detachably connected together by means of removable pintles or pivot pins, permitting the links to be readily disconnected and separated.

Sprocket chains of the type described herein are especially adapted for use in conveyers of all kinds and are almost universally employed in coal handling machinery. When operating in the anthracite coal regions the chains are subjected to the destructive corrosive action of the sulfuric mine water which adds very materially to the wear or attrition occurring at the friction surfaces between the ends of the links and between the links and pintles. This erosive action, together with the frictional wear, causes the ends or locking heads of the links to become loose, which results in uneven tension or pull upon the connecting parts, and these undue and unequal stresses not only greatly shorten the life of the chain but cause frequent breakage of links which would otherwise be able to operate for a considerably longer period.

It is obvious that a worn chain orworn portions could be made to operate with. safety and satisfactorily for an extended period if some means were provided for taking up the looseness and thereby obviating the unequal strains which resulted from the wear of the parts. In the case of riveted chains, this result can only be obtained by cutting off the heads of the rivet pins with a cold chisel and replacing with shorter new pins or by placing washers over the new pins before their ends are riveted or headed in the links. The expense and loss of time incurred by this method are prohibitive.

The purpose of my invention is to provide means for readily adjusting the links to compensate for the wear in the so-called rivetless type or those in which the links are detachably connected by means of removable pins or pintles. It will be evident to engineers that the closer the connecting joints Specification of Letters Patent.

Patented Nov. 15, 1921.

1921. Serial No. 451,013.

on a chain are maintained in operation, the greater the efiiciency by reason of the equalization of strainsthroughout the section of the links and pins, thereby decreasing the liability of breakage; also that the wear is greatly diminished in a closely jointed chain wherein gritty material and foreign substances are prevented entrance.

In the detailed description which follows, I shall refer to the accompanying illustrative drawings, in whichFigure .1 is a plan vlew, partly in section of one form of chain embodying my invention; Fig. 2 is a side elevation thereof; Fig. 3 is a plan view of a portion of such a chain with the links in assembling position; Fig. 1 is a fragmentary side elevation showingthe manner of inserting a pin; Fig. 5 is a perspective view of the .pin employed as the connecting pintle in the preceding figures; Fig. 6 is a fragmentary view of the connected head ends of the links with one of my take-up devices or detachable washers in position; Fig. is a side elevation of the latter; Fig. 8 is a perspective view of my preferred form of wear take-up device or detachable washer; Fig. 9 is a plan view of the arrangement shown in Fig. l but with the pins or pintles provided with flattened locking surfaces upon both sides of the bearing portion and also having extension or outbearings to adapt the chain for outside drive over double flanged sprocket wheels; Fig. 10, is a plan view of the latter showing the links moved into collapsed position; Fig. 11 is a fragmentary side elevation with the center links turned.

into positions at right angles to that shown in Fig. 10 for the insertion or removal of the pintles; Fig. 12 is a longitudinal sec- 'tional view on the line 1212 of Fig. 11; Fig. 12 is a side elevation of the pintle used in the arrangement shown in Fig. 12: Fig. 13 is a plan view, partly in section, of a modified form of my invention; Fig. 1.4 is a side elevation of the same; Fig. 15 is a fragmentary horizontal longitudinal sectional view of the arrangement shown in Fig. 13 with the links moved into collapsed position; Fig. 16 is a side elevationof the same; and Fig. 17 is a fragmentary plan view of the form shown in Figs. 13 to 16 with my take-up washer in position.

The chain comprisesalternate single or center links 1- and pairs of parallel side links 2 connected by pivot pins or pintles 8.

The single or center links 1 are provided with projecting portions or bosses 1 at each end extending symmetrically upon either side, so that there is a recess extending along the sides of the link between the bosses or heads. These links may have a single slot extending from end to end or may be provided with a central transverse web 6. The side links 2, are thinner than the center links and are provided at each end with bosses 2 upon their inner sides, so that the links may be said to be recessed upon their inner sides betweenthe bosses or heads. These links also may have a single slot extending from end to end or may be provided with a central transverse web 7.

In the form of my invention illustrated in Figs. 1 to 5 I employ a pivot pin or pintle shown in Fig. 5, having a cylindrical body 8 with oblong rectangular ends or heads 9 and a single squared lug 1O projecting laterally beyond the side edge of the adjacent head. By thus extending the lug 10, beyond the periphery of the bearing portion 8, a single lug is sufficient to securely lock the pin against rotation.

In order to assemble the parts, the single linksl upon either side of a pair of side links 2, are slid inwardly until the bosses 1", are within the recesses between the bosses 2 of the side links, the latter being moved together until they bear against the center links as shown in Fig. 3. The pivot pins or pintles are then held with the longer axes of their heads 9 parallel with the links as illustrated in Fig. 4, and are then inserted through the links until stopped by the lugs 10. The pins are then turned through an angle of 90, bringing the lugs 10 into aline ment with the slots. The links 1 are then pulled outwardly in opposite directions, thereby forcing the side links outwardly until the heads of thelinks are in transverse alinement and the pivot pins bear against the ends of the slots, as shown in Fig. 1.

'with the lug 10 engaging the upper and lower walls of the slot. thereby securely locking the pin against rotation. By this construction and combination of parts, 1 am enabled to assemble the links and insert the pivot pins without turning the links at an angle to each other and by merely drawing them toward eachother a distance sutlicient to inclose the bosses 1 of the single links within the recesses of the side links. The pins may then be inserted and turned 90 because the distance between the inner sides of the lug 10 and the opposite head 9 is the same or slightly greater than the combined widths of the links when they are in the collapsed assembling position illustrated in Fig. 3. In so far as I am aware I am the first to provide a chain which may be assembled in this manner and the advantages will be appreciated by engineers and those who have had experience in manipulating conveyer chains of this type. lvloreover, by this construction the pivot pins are locked against irotatio'n without the necessity of forming notches in the side links to receive the heads of the pins, which weaken the heads and render them liable to fracture.

In Figs. 9 to 12, I have employed pivot pins having squared or flattened portions at each side of the bearing surface which eugage the upper and lower walls of the slots to prevent turning. One form of this pin is shown in Fig. 12. It will be observed that the cylindrical bearing surface 8 between the squared or flattened locking faces 10 is shorter than the combined width of the links when they are in the collapsed position shown in Fig. 10, and consequently the single links 1 must be turned 90 and then brought toward the center of the side links, as indicated in Fig. 11, in order to bring the thin central portion of the single links alongside of the thinner central portions of the ide links. The side links may then be brought closer together until the combined width of the links is slightlyless than the length of the bearing portion 8 of the pins, as shown in Fig. 12, and after the pins are inserted the links may be swung back into longitudinal alinement and then moved outwardly into the position indicated in Fig. 9, the pins being'drawn into the ends of the slots and locked against rotation by the engagement of the squared faces 1O with the opposite walls of the slots in both side links. If desired, the pins may be formed with extensions or outbearings 15, as shown in Figs. 9 and 10, to adapt the chain for outside drive with double flanged sprocket wheels.

As pointed out above, the joints of the chains are subjected to rapid wear due to friction and also to the corrosive action of the mine water, the greatest wear taking place between the engaging surfaces of the heads of the links. The resulting looseness of the joints causes an increased wear and produces unequal strains which greatly decrease the life of the chain and cause frequent breakage of the links. To overcome this defect, 1 provide a takeup device which may be readily applied to any of the links that have become worn. The preferred form is shown in Fig. 8 and consists of a yokeshaped washer 20 having the ends of the arms bent outwardly into lugs 20 which are adapted to bear against the edges of the heads of the pivot pins.

When the links have become worn, washers of the proper thickness are slid over the pivot pins between the links and the pin heads. The links are first moved into collapsed position shown in Figs. 3, l0 and 12, so that the pins will project beyond'the sides I of the links and the washers are then sh ped overthe projecting ends of the pins. Wlien the links are moved outwardly into normal position the washers will be locked by the engagement of the lugs 20 against the edges of the heads of the pins as shown in Figs. 6, 7 and 17. The washers may be made of different thicknesses to suit different degrees of wear so that the proper compensating adjustment may be made to take up all looseness in various parts of the chain.

It is sometimes desirable to employ pintles or pivot pins havin smooth unbroken cylindrical body portlons and to lock them against turning by means of the heads. I have devised such a chain in which my takeup washers may be used to take up looseness due to wear and have illustrated the same in Figs. 13 to 16 inclusive which show the different positions assumed by the parts in assembling or dismantling the links. I provide each side link with a single transverse notch 2 and in assembling the parts, I place the notches at opposite ends as illustrated in Fig, 13. When the links are to be assembled the single center links 1 are slid inwardly until the bossed ends 1 are within the recesses of the side links 2, just as previously described in connection with the construction illustrated in Figs. 1 to 3. The pins may then be inserted in the manner previously described by first turning the heads so that their longitudinal axes are parallel with the axes of the slots, as shown in Fig. 16 and after they are inserted, they may be turned through 90 to bring the heads into alinement with the notches 2 as illustrated in Fig. 15. When the links are then pulled outwardly into normal operative position the heads which are opposite the notches will be drawn thereinto in the manner shown in Fig. 13.

When the links become worn the center links are slid inwardly into the position for assembling, illustrated in Fig. 15, so that the side links may be moved close together and a washer of the form illustrated in Fig. 8 is then slidunder the head of the pivot pin on the side opposite from the notch, or in otherwords, between the head of the pivot and the smooth or unbroken head of the side links. When the parts are again moved out into normal extended position, the washers will be held and locked against movement by the engagement of the outstanding lugs 2O which bear against the side faces of the heads of the pivot pins as illustrated in Fig. 17 This form has the advantage of using the simplest form of pintle and which may be reversed when worn on one side and may be readily adjusted to take up wear by inserting my washers of the desiredthickness. Furthermore, as the side links have only one notch ateach end and as the notches alternate upon opposite sides, the chain is much stronger than priorchains in which both ends of each of the sidelinks were notched.

I have described in detail the various forms illustrated in the accompanying drawings for the purpose of definitely disclosing my invention but it will be obvious to engineers that various changes and modifications thereof may be made without in any manner departing from this invention.

I claim 1. A chain comprising center links having thickened end portions projecting symmetrically upon opposite sides of the central body portion, and pairs of side links provided with opposite end portions thickened upon the inner sides, pintles adapted to extend through the links and having heads shaped to be inserted through the slots of the links when turned into registry therewith, the body portions of said pintles being cylindrical and having opposite flattened surfaces to engage the inner faces of the slots when the thickened ends of proximate center and side links, are brought into transverse alinement, and a yoke-shaped take-up member adapted to embrace the pintle body, the yoke-arms having end lugs adapted to bear against the edge of the adjacent head of the pintle.

2. A chain comprising alternate center links and complementary pairs of side links, said links having thickened end portions permitting the side links to be brought closer together when the center links are slid inwardly into assemblingposition, pintles having locking faces adapted to engage the in ner surfaces of the link slots when the links are in normal extended position and a cylindrical bearing portion extending to the outer sides of the side links when the parts are in assembling position, and a take-up member adapted to slip over the pintle when the parts are in assembling position and pro vided with end lugs adapted to be brought over the ends of the pintles when the links are drawn outwardly into normal position.

3. A chain comprising center links having thickened end portions projecting symmetrically upon opposite sides of the central body portion, and pairs of side links provided with opposite end portions thickenedupon the inner sides, pintles adapted to expintle body, the yoke-arms having end lugs adapted to bear against the edge of the adjacent head of the pintle.

4. A chain comprising center links and complementary pairs of side links, said links being so shaped that the Width of the chain may be decreased When the center links are slid longitudinally between the side links,

and headed pintles adapted to pass through the slots in the links when collapsed, said 10 pintles being provided With'a laterallyprojecting lug between the heads for engaging the inside Walls of the links to prevent the pintles from turning When in normal coupled position. I

In testimony whereof I affix my signature.

JAMES o. LAW. 

